+struct ref_list {
+ struct ref_list *next;
+ unsigned char sha1[20];
+ char name[FLEX_ARRAY];
+};
+
+static const char *parse_ref_line(char *line, unsigned char *sha1)
+{
+ /*
+ * 42: the answer to everything.
+ *
+ * In this case, it happens to be the answer to
+ * 40 (length of sha1 hex representation)
+ * +1 (space in between hex and name)
+ * +1 (newline at the end of the line)
+ */
+ int len = strlen(line) - 42;
+
+ if (len <= 0)
+ return NULL;
+ if (get_sha1_hex(line, sha1) < 0)
+ return NULL;
+ if (!isspace(line[40]))
+ return NULL;
+ line += 41;
+ if (line[len] != '\n')
+ return NULL;
+ line[len] = 0;
+ return line;
+}
+
+static struct ref_list *add_ref(const char *name, const unsigned char *sha1, struct ref_list *list)
+{
+ int len;
+ struct ref_list **p = &list, *entry;
+
+ /* Find the place to insert the ref into.. */
+ while ((entry = *p) != NULL) {
+ int cmp = strcmp(entry->name, name);
+ if (cmp > 0)
+ break;
+
+ /* Same as existing entry? */
+ if (!cmp)
+ return list;
+ p = &entry->next;
+ }
+
+ /* Allocate it and add it in.. */
+ len = strlen(name) + 1;
+ entry = xmalloc(sizeof(struct ref_list) + len);
+ hashcpy(entry->sha1, sha1);
+ memcpy(entry->name, name, len);
+ entry->next = *p;
+ *p = entry;
+ return list;
+}
+
+static struct ref_list *get_packed_refs(void)
+{
+ static int did_refs = 0;
+ static struct ref_list *refs = NULL;
+
+ if (!did_refs) {
+ FILE *f = fopen(git_path("packed-refs"), "r");
+ if (f) {
+ struct ref_list *list = NULL;
+ char refline[PATH_MAX];
+ while (fgets(refline, sizeof(refline), f)) {
+ unsigned char sha1[20];
+ const char *name = parse_ref_line(refline, sha1);
+ if (!name)
+ continue;
+ list = add_ref(name, sha1, list);
+ }
+ fclose(f);
+ refs = list;
+ }
+ did_refs = 1;
+ }
+ return refs;
+}
+
+static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
+{
+ DIR *dir = opendir(git_path("%s", base));
+
+ if (dir) {
+ struct dirent *de;
+ int baselen = strlen(base);
+ char *path = xmalloc(baselen + 257);
+
+ memcpy(path, base, baselen);
+ if (baselen && base[baselen-1] != '/')
+ path[baselen++] = '/';
+
+ while ((de = readdir(dir)) != NULL) {
+ unsigned char sha1[20];
+ struct stat st;
+ int namelen;
+
+ if (de->d_name[0] == '.')
+ continue;
+ namelen = strlen(de->d_name);
+ if (namelen > 255)
+ continue;
+ if (has_extension(de->d_name, ".lock"))
+ continue;
+ memcpy(path + baselen, de->d_name, namelen+1);
+ if (stat(git_path("%s", path), &st) < 0)
+ continue;
+ if (S_ISDIR(st.st_mode)) {
+ list = get_ref_dir(path, list);
+ continue;
+ }
+ if (read_ref(git_path("%s", path), sha1) < 0) {
+ error("%s points nowhere!", path);
+ continue;
+ }
+ list = add_ref(path, sha1, list);
+ }
+ free(path);
+ closedir(dir);
+ }
+ return list;
+}
+
+static struct ref_list *get_loose_refs(void)
+{
+ static int did_refs = 0;
+ static struct ref_list *refs = NULL;
+
+ if (!did_refs) {
+ refs = get_ref_dir("refs", NULL);
+ did_refs = 1;
+ }
+ return refs;
+}
+